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A build performs an assortment of tasks, often reusing existing libraries and tools. The plugin mechanism in sbt enables reuse, by adding libraries to the metabuild. This works well for lightweight tasks, or for integrating with CLI tools like gpg . However, adding more libraries to the metabuild may not be desirable or possible. For example, tools like Scalafix or Coursier are written in some…
Hi everyone. On behalf of the tree-sitter-scala project, I am happy to announce tree-sitter-scala 0.26.2. The first two segments of the version number comes from the tree-sitter-cli that was used to generate the parser, and the last segment is our actual version number. For example, tree-sitter-scala 0.26.2 uses tree-sitter 0.26.x. 
 About tree-sitter-scala 
 tree-sitter-scala is a Scala…
The headline features of sbt 1.12.15 and 2.0.6 are: 
 
 Vulnerability fix for remote code execution via server when serverConnectionType is set to Tcp 
 
 See also sbt 2.0 change summary for the details on sbt 2.0.
I am Eugene Yokota (@eed3si9n on Mastodon and GitHub ), a software engineer with years of experience working on Scala tooling. Most recently, I was an L6 (equivalent to Staff Engineer) at Netflix’s Productivity, Tooling, and Reliability team that maintained Algo monorepo for recommendation algorithms (See 3 years at Netflix ). Previously I was a Staff Engineer at Twitter’s EE…
The headline features of sbt 2.0.5 are: 
 
 In-process test ClassLoader change 
 update task performance improvements 
 Common settings bug fix 
 
 See also sbt 2.0 change summary for the details.
The headline features of sbt 2.0.4 are: 
 
 Forked runs in current directory 
 Caching-related bug fixes 
 Memory improvement on large builds 
 
 See also sbt 2.0 change summary for the details.
Jar Jar Abrams 1.17.0 and sbt-assembly 2.4.0 are released. 
 Jar Jar Abrams is an experimental extension to Jar Jar Links, intended to shade Scala libraries.
I joined the tooling team for Netflix’s personalization and recommendation group in January 2023. Three years later, July 13, 2026 was my last day. I got to be part of two great organizations, AI for Member Systems and AI Platform, and experience Netflix’s culture of excellence and diversity firsthand.
The headline features of sbt 1.12.14 and 2.0.3 are: 
 
 Backport of CVE-2026-26032 fix for Ivy (while sbt might not be affected) 
 Update to Jawn 1.7.0 for CVE-2026-59990 and CVE-2026-61814 fixes 
 
 See also sbt 2.0 change summary for the details.
The headline features of sbt 2.0.2 are: 
 
 Metabuild resolution fix 
 Build pipelining fix 
 Remote cache timeout fix 
 sbtn stdout replaying fix 
 
 See also sbt 2.0 change summary for the details.
The headline features of sbt 2.0.1 are: 
 
 Incremental test performance improvement 
 sbt runner fixes 
 Global plugin loading fix 
 Coursier 2.1.25-M26 
 
 See also sbt 2.0 change summary for the details.
The headline feature of sbt 1.12.13 is: 
 
 Fixes file permissions issue 
 
 See also 1.12.0 release note for the details on 1.12.x features.
A few days ago, Maven Central Repository has introduced Maven Central Publishing Limits . See Brian Fox’s Open Publishing, Commercial Scale for the background: 
 
 A maintainer publishing normal releases for an open source project is one thing. A large commercial entity using Maven Central as the last-mile distribution channel for SDKs, agents, generated clients, integrations, or…
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 2.0.0. sbt 2.0 is a new major series of sbt, based on Scala 3 constructs and Bazel-compatible cache system. 
 sbt 2.x is released under Semantic Versioning, and the plugins are expected to work throughout the 2.x series. Please try it out, and report any issues you might come across.
This is a blog post on sbt 2.x development, continuing from sbt 2.x remote cache , sudori part 4 , part 5 , part 7 etc. 
 background 
 Hashing comes up while developing sbt, often in the context of caching and incremental compilation. Basically when we have either a list of files or some parameters, we want to figure out if the calculation has ever been done before. That require hashing…
Key changes since 2.0.0-RC12 
 
 Scala 3.8.3 
 Fixes build.sbt loading from subdirs 
 Fixes cache and incremental compilation interference 
 Fixes incremental test with arguments 
 Atomic file writing and copying 
 Execution log 
 
 See https://github.com/sbt/sbt/releases/tag/v2.0.0-RC13
The headline feature of sbt 1.12.11 is: 
 
 Rollback eviction error in Test 
 
 See also 1.12.0 release note for the details on 1.12.x features.
The headline feature of sbt 1.12.10 is: 
 
 Update to log4j 2.25.4, fixing CVE-2026-34477 , CVE-2026-34478 , CVE-2026-34479 , and CVE-2026-34480 
 Backport of eviction error in Test configuration 
 
 See also 1.12.0 release note for the details on 1.12.x features.
This is a follow-up of sbt and the miners of the wild west , in which I described the story of sbt/sbt getting listed on a crypo-based, open source bounty program called Gittensor , and subsequently getting a high volume of contributions from dozens of users, many of whom using AI tools. Well, I’m shutting it all down.
Hi everyone. On behalf of the tree-sitter-scala project, I am happy to announce tree-sitter-scala 0.25.1 and 0.26.0. The first two segments of the version number comes from the tree-sitter-cli that was used to generate the parser, and the last segment is our actual version number. For example, tree-sitter-scala 0.26.0 uses tree-sitter 0.26.x. 
 About tree-sitter-scala 
 tree-sitter-scala…
Key changes since 2.0.0-RC11 
 
 Fixes .previous expansion 
 Adds addDependencyTreePlugin shim 
 
 See https://github.com/sbt/sbt/releases/tag/v2.0.0-RC12
Key changes since 2.0.0-RC9 
 
 JDK 17 + Scala 3.8.2 in metabuild 
 Dependency mode 
 More robust task caching 
 Slight tweak of the prompt 
 
 See https://github.com/sbt/sbt/releases/tag/v2.0.0-RC10 for the full details.
The headline feature of sbt 1.12.8 is: 
 
 Source dependency checkout directory fix 
 
 See also 1.12.0 release note for the details on 1.12.x features.
The headline feature of sbt 1.12.7 is: 
 
 CVE-2026-32948 fix 
 
 See also 1.12.0 release note for the details on 1.12.x features. 
 Note : sbt 1.12.7 has a source dependency bug. Use sbt 1.12.8 instead.
The headline feature of sbt 1.12.6 is: 
 
 Coursier 2.12.25-M24 update 
 log4j 2.25.3 update 
 
 See also 1.12.0 release note for the details on 1.12.x features.
Hi everyone. On behalf of the tree-sitter-scala project, I am happy to announce tree-sitter-scala 0.24.1 and 0.25.0. The first two segments of the version number comes from the tree-sitter-cli that was used to generate the parser, and the last segment is our actual version number. For example, tree-sitter-scala 0.25.0 uses tree-sitter 0.25.x. 
 About tree-sitter-scala 
 tree-sitter-scala…
The headline feature of sbt 1.12.5 is: 
 
 sbtn update to print out errors when sbt server fails to start 
 backport of runner script fixes 
 
 See also 1.12.0 release note for the details on 1.12.x features.
The headline feature of sbt 1.12.4 is: 
 
 Scala compiler bridge resolution fix to respect scalaOrganization 
 a backport of runner script fix 
 
 See also 1.12.0 release note for the details on 1.12.x features.
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 2.0.0-RC8, a beta version of sbt 2.x. sbt 2.0 is a new version of sbt, based on Scala 3 constructs and Bazel-compatible cache system. 
 Please try it out, and report any issues you might come across. Note : sbt 2.0.0-RC9 will keep binary compatibility with 2.0.0 and 2.x. 
 Key changes since 2.0.0-RC8 
 
 JDK 17 +…
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 1.12.3. This is the twelfth feature release of sbt 1.x, a binary compatible release focusing on new features. sbt 1.x is released under Semantic Versioning, and the plugins are expected to work throughout the 1.x series. Please try it out, and report any issues you might come across. 
 The headline feature of sbt 1.12.3 is:…
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 1.12.2. This is the twelfth feature release of sbt 1.x, a binary compatible release focusing on new features. sbt 1.x is released under Semantic Versioning, and the plugins are expected to work throughout the 1.x series. Please try it out, and report any issues you might come across. 
 The headline feature of sbt 1.12.2 is:…
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 1.12.1. This is the twelfth feature release of sbt 1.x, a binary compatible release focusing on new features. sbt 1.x is released under Semantic Versioning, and the plugins are expected to work throughout the 1.x series. Please try it out, and report any issues you might come across. 
 The headline feature of sbt 1.12.1 is:…
small village of sbt 
 I’m a volunteer maintainer/core dev of sbt and Zinc, the toolchain that powers the Scala programming language, which is a multi-paradigm language targetting JVM, JS, and native. Scala itself has been around for 20 years, and since Twitter’s adoption in 2009 it’s been used by Apache Spark, LinkedIn, Morgan Stanley, ING, Airbnb, Spotify, Netflix, etc.…
Eval 0.3.2 is released. Eval evaluates Scala 3 code. See https://eed3si9n.com/eval/ for details. 
 Eval 0.3.2 adds Scala 3.8.1 support: 
 
 Register source name by @som-snytt in #22 
 Align the initial runId with the one used in the compiler for Scala 3.8.1 by @jchyb in #26 

Hi everyone. On behalf of the sbt project, I am happy to announce sbt 2.0.0-RC8, a beta version of sbt 2.x. sbt 2.0 is a new version of sbt, based on Scala 3 constructs and Bazel-compatible cache system. 
 Please try it out, and report any issues you might come across. Note : sbt 2.0.0-RC8 will keep binary compatibility with 2.0.0 and 2.x. 
 Key changes since 2.0.0-RC7 
 See…
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 1.12.0. This is the twelfth feature release of sbt 1.x, a binary compatible release focusing on new features. sbt 1.x is released under Semantic Versioning, and the plugins are expected to work throughout the 1.x series. Please try it out, and report any issues you might come across. 
 The headline features of sbt 1.12.0…
I’m going to try to work on something small everyday during december. see the original December Adventure . 
 my goals: 
 
 make bad dub techno 
 work on sbt 2.x 

Hi everyone. On behalf of the sbt project, I am happy to announce sbt 1.12.0-RC1. This is the twelfth feature release of sbt 1.x, a binary compatible release focusing on new features. sbt 1.x is released under Semantic Versioning, and the plugins are expected to work throughout the 1.x series. Please try it out, and report any issues you might come across. 
 The headline features of sbt 1.12.0…

 
 YouTube: https://www.youtube.com/playlist?list=PLSUh6oJ5ZotX_KYqq9nBcwQWpDC9WwWES 

This is a blog post on sbt 2.x development, continuing from sbt 2.x remote cache , sudori part 4 , part 5 etc. I work on sbt 2.x in my own time with collaboration with the Scala Center and other volunteers, like Billy at EngFlow. In this post, I want to highlight the perf improvement work I attempted in sbt 2.0.0-RC7 , which was released yesterday. 
 no-op performance regression 
 Besides…
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 2.0.0-RC7, a beta version of sbt 2.x. sbt 2.0 is a new version of sbt, based on Scala 3 constructs and Bazel-compatible cache system. 
 Please try it out, and report any issues you might come across. Note : sbt 2.0.0-RC7 will keep binary compatibility with 2.0.0 and 2.x. 
 Key changes since 2.0.0-RC6 
 See…
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 1.12.0-M2. This is the twelfth feature release of sbt 1.x, a binary compatible release focusing on new features. sbt 1.x is released under Semantic Versioning, and the plugins are expected to work throughout the 1.x series. Please try it out, and report any issues you might come across. 
 The headline features of sbt 1.12.0…
Expecty 0.17.1 is released. Expecty brings power assert (or power assertion) to Scala. It was originally implemented by Peter Niederwieser who implemented the original power assertion Spock in Groovy. It had gone dormant for a while, and I forked it in 2018 , and started publishing it against modern build matrix like Scala 2.12, 2.13, 3.x, JVM, JS, and Native.
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 1.12.0-M1. This is the twelfth feature release of sbt 1.x, a binary compatible release focusing on new features. sbt 1.x is released under Semantic Versioning, and the plugins are expected to work throughout the 1.x series. Please try it out, and report any issues you might come across. 
 The headline features of sbt 1.12.0…
In this post, I want to look into the incremental compilation of Scala 3, or the apparent problem associated with it. The incremental compilation on Scala 2.12 or 2.13 has been fairly stable, but for some reason it’s more fragile on Scala 3.x in my experience. We will investigate the cause and attempt to fix it as scala/scala3#24171 .
Hi everyone. On behalf of the sbt project, I’m happy to announce that sbt 1.11.7 patch release is available. 
 The headline features of sbt 1.11.7 are: 
 
 Launcher 1.5.1 to fix sbt 0.13 support, including on setup-sbt action v1 
 JDK 25 warning workaround by adding JDK flags in sbt runner 
 Backport of JDK 25 JEP-512/JEP-445 Main run 
 
 Full release note is here…
Hi everyone. On behalf of the sbt project, I am happy to announce sbt 2.0.0-RC6, a beta version of sbt 2.x. sbt 2.0 is a new version of sbt, based on Scala 3 constructs and Bazel-compatible cache system. 
 Please try it out, and report any issues you might come across. Note : sbt 2.0.0-RC6 will keep binary compatibility with 2.0.0 and 2.x. 
 Key changes since 2.0.0-RC5 
 See…
Hi everyone. On behalf of the sbt project, I’m happy to announce that sbt 1.11.6 patch release is available. 
 The headline features of sbt 1.11.6 are: 
 
 Launcher 1.5.0 
 Internal dependency classpath fix 
 sbtn client-side run fix 
 
 Full release note is here - https://github.com/sbt/sbt/releases/tag/v1.11.6 . See 1.11.0 release note for the details on 1.11.x…
Hi everyone. On behalf of the sbt project, I’m happy to announce that sbt 1.11.5 patch release is available. 
 The headline features of sbt 1.11.5 are: 
 
 Scala 3.8.0 (currently nightly) support 
 Scala Nightly repository support 
 Central Repository publishing improvements 
 sbt --jvm-client 
 sbtn improvements 
 
 Full release note is here -…
I went to Scala Days 2025 at EPFL this week to give a talk on sbt 2.0. 
 
 slides